Partial Packet Duplication: Control of Fade and Non-Fade Duration Outages Using Matrix Exponential Distributions

We propose partial packet duplication; when cellular dual connectivity is available we propose to duplicate only during some portion of the time as needed. This satisfies reliability constraints defined as (1) the probability of fades staying shorter than a certain duration and (2) the probability of non-fades (i.e., time back above the SINR threshold) lasting longer than a certain duration. Fade durations and non-fade durations have been estimated in the literature to fit exponential distributions. We also choose exponential random variables to control duplication processes, which allows Markov chain modeling of the entire process. Using matrix exponential distribution formulations of the Markov chain in the context of partial packet duplication, we fully describe the partial packet duplication behavior, examine asymptotic performance, and define ranges of duplication parameters that meet both fade and non-fade duration constraints. Then we choose the best parameters that minimize resources used on the secondary link for packet duplication.